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XRT81L27
á
SEVEN CHANNEL E1 LINE INTERFACE UNIT WITH CLOCK RECOVERY
REV. 1.1.0
4
26
TGND_4
Gnd
Transmitter 4 Supply Ground
27
PDTx_6
I-H
Power-down Transmitter 6: (see pin 6)
28
TTIP_6
O
Transmitter 6 Tip Output: Positive bipolar data output to the line.
29
TVDD_6
Vdd
Transmitter 6 Positive Supply(3.3V± 5%)
30
TRING_6
O
Transmitter 6 Ring Output: Negative bipolar data output to the line.
31
TGND_6
Gnd
Transmitter 6 Supply Ground
32
MODE
I-L
Mode Control Input:
This pin is used to select Hardware or Host Mode control of the device.
Tie “Low” to select Host Mode
"High" to select Hardware Mode.
33
RClk_4
O
Receiver 4 Clock Output:
34
RNEG_4
LCV_4
O
Receiver 4 Negative Data Output:
In Dual-Rail mode, this signal is the receive n-rail output data.
Line Code Violation Output:
In Single-Rail mode, this signal outputs a "High" for one clock cycle to
indicate a code violation is detected in the received data.
If AMI coding is selected, every bipolar violation received will cause this
pin to go "High".
35
RPOS_4
RDATA_4
O
Receiver 4 Positive Data Output:
In Dual-Rail mode, this signal is the receive p-rail output data.
Receiver 4 NRZ Data Output:
In Single-Rail mode, this signal is the receive output data
36
LOS_4
O
Receiver 4 Loss of Signal: (see pin 2)
37
TClk_4
I
Transmitter 4 Clock Input: E1 rate at 2.048MHz ± 50ppm.
38
TPOS_4
TDATA_4
I
Transmitter 4 Positive Data Input:
In Dual-Rail mode, this signal is the p-rail input data for transmitter 4.
Transmitter 4 NRZ Data Input:
In Single-Rail mode, this signal is used as the NRZ input data
39
TNEG_4
CODE_4
I-L
Transmitter 4 Negative Data Input:
In Dual-Rail mode, this signal is the n-rail data input for transmitter 4.
In Single-Rail mode (pin 69=1) and with this pin tied "High", input data
at the transmit input is encoded in HDB3 format and the substitution
code in the corresponding receive channel will be removed.
Tie this pin "Low" to enable AMI encoding and decoding.
40
TAOS_4
I-L
Transmit All Ones Channel_4:
This pin is set to insert AMI all ones data to the line using MCLK as refer-
ence.
In Host Mode, this pin can be left unconnected.
41
VDD
Vdd
Digital Positive Supply(3.3V± 5%).
42
GND
Gnd
Digital Supply Ground.
PIN DESCRIPTIONS
NOTE: I -H indicates an input pin with a 50k
pull-up Resistor, I-L indicates an input pin with a 50k pull-down resistor.
PIN #NAME
TYPE
DESCRIPTION